Lightning arresters are installed in gas insulation switchgears (“GIS”), such as those used in power stations or substations, to protect electrical equipment from abnormal voltages which may arise from lightning strikes. Known lightning arresters, used for voltages below 66 kV, have a standard upper plug interface and an overvoltage protection device disposed in an interior of the arrester. The overvoltage protection device has ZnO resistance pieces. Some known lightning arresters also have a pressure relief function, however, the electrical field distribution in such a known arrester is very uneven, which can impair the reliability of arrester performance and long-term running stability.